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<td><b><dl><dt>Berkeley DB Reference Guide:<dd>Upgrading Berkeley DB Applications</dl></b></td>
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<p align=center><b>Release 4.0: log_XXX</b></p>
<p>The C API for the Berkeley DB Logging subsystem was reworked in the 4.0
release as follows:</p>
<table border=1 align=center>
<tr><th>Historic functional interface</th><th>Berkeley DB 4.X method</th></tr>
<tr><td>log_archive</td><td><a href="../../api_c/log_archive.html">DB_ENV-&gt;log_archive</a></td></tr>
<tr><td>log_file</td><td><a href="../../api_c/log_file.html">DB_ENV-&gt;log_file</a></td></tr>
<tr><td>log_flush</td><td><a href="../../api_c/log_flush.html">DB_ENV-&gt;log_flush</a></td></tr>
<tr><td>log_get</td><td><a href="../../api_c/log_cursor.html">DB_ENV-&gt;log_cursor</a>, <a href="../../api_c/logc_get.html">DB_LOGC-&gt;get</a>, <a href="../../api_c/logc_close.html">DB_LOGC-&gt;close</a></td></tr>
<tr><td>log_put</td><td><a href="../../api_c/log_put.html">DB_ENV-&gt;log_put</a></td></tr>
<tr><td>log_register</td><td>DB_ENV-&gt;log_register</td></tr>
<tr><td>log_stat</td><td><a href="../../api_c/log_stat.html">DB_ENV-&gt;log_stat</a></td></tr>
<tr><td>log_unregister</td><td>DB_ENV-&gt;log_unregister</td></tr>
</table>
<p>Applications calling any of these functions should update their calls
to use the enclosing <a href="../../api_c/env_class.html">DB_ENV</a> handle's method (in all cases other
than the log_get call, this is easily done as the first argument to the
existing call is the correct handle to use).</p>
<p>Application calls to the historic log_get function must be replaced
with the creation of a log file cursor (a <a href="../../api_c/logc_class.html">DB_LOGC</a> object), using
the <a href="../../api_c/log_cursor.html">DB_ENV-&gt;log_cursor</a> method, calls to the <a href="../../api_c/logc_get.html">DB_LOGC-&gt;get</a> method to retrieve log
records and calls to the <a href="../../api_c/logc_close.html">DB_LOGC-&gt;close</a> method to destroy the cursor.  It
may also be possible to simplify some applications.  In previous
releases of Berkeley DB, the DB_CURRENT, DB_NEXT, and DB_PREV flags to the
log_get function could not be used by a free-threaded <a href="../../api_c/env_class.html">DB_ENV</a>
handle.  If their <a href="../../api_c/env_class.html">DB_ENV</a> handle was free-threaded, applications
had to create an additional, unique environment handle by separately
calling <a href="../../api_c/env_open.html">DB_ENV-&gt;open</a> without specifying <a href="../../api_c/env_open.html#DB_THREAD">DB_THREAD</a>.  This
is no longer an issue in the log cursor interface, and applications may
be able to remove the now unnecessary creation of the additional
<a href="../../api_c/env_class.html">DB_ENV</a> object.</p>
<p>Finally, the <a href="../../api_c/log_stat.html">DB_ENV-&gt;log_stat</a> call has been changed in the 4.0 release
to take a flags argument.  To leave their historic behavior unchanged,
applications should add a final argument of 0 to any calls made to
<a href="../../api_c/log_stat.html">DB_ENV-&gt;log_stat</a>.</p>
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